Question: Seat belt use The proportion of drivers who use seat belts depends on things like age (young people are more likely to go unbelted) and gender (women are more likely to use belts). It also depends on local law. In New York City, police can stop a driver who is not belted. In Boston at the time of the study, police could cite a driver for not wearing a seat belt only if the driver had been stopped for some other violation. Here are data from observing random samples of female Hispanic drivers in these two cities:
City Drivers Belted
New York 220 183
Boston 117 68
(a) Calculate the standard error of the sampling distribution of the difference in the proportions of female Hispanic drivers in the two cities who wear seat belts. What information does this value provide?
(b) Construct and interpret a 95% confidence interval for the difference in the proportions of female.